Projects currently under way or soon to be initiated include the following: A. Establishment, characterization and studies of a human melanoma lung metastasis model in athymic mice, B. Development and pharmacologic studies of a short-term lung perfusion model for chemosensitivity studies using human melanoma lung metastases, C. Immunological and tumor biology studies in new strains of mice with multiple immune defects, D. Studies of lymphoma development in beige-nude mice, E. Chemosensitivity studies of new drug candidates in human lung cancer systems, F. Establishment of a panel of human soft-tissue sarcomas and osteogenic sarcomas in nude mice and in culture, G. Ultrastructural studies of human cancer cell lines, H. Physiology, pharmacology and toxicology of the pulmonary Clara cell, I. Cellular/molecular factors in cell death by chemically reactive metabolites, J. Cellular dynamics and structural/physiological consequences of drug-induced damage of discrete extrahepatic cell populations, and K. Collaborative ultra-structural studies with other DTP laboratories. More detailed descriptions of each of these projects are presented herein.